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Simple Summary: Arylalkylamine N-acetyltransferase (AANAT) is an enzyme that regulates the production of melatonin, a hormone that is essential for organisms to maintain circadian and annual rhythmic behavior. The AANAT gene has undergone gene duplication and inactivation during evolution. Nevertheless, the majority of mammals retain a solitary copy of AANAT within the biological genome, and the mechanisms by which this gene responds to environmental stimuli remain poorly understood. To address this issue, we investigated the adaptive evolution of AANAT at both the gene and protein levels. Our study revealed the presence of multiple mutation sites within the gene encoding AANAT, with variation in the structure of the AANAT protein observed across different geographic populations. We identified a positive selection of AANAT in populations residing at higher latitudes. Furthermore, individuals exhibiting longer hibernation periods displayed significantly higher catalytic efficiency of the AANAT enzyme compared to those with minimal hibernation behavior, suggesting a potential association between AANAT and hibernation rhythms. This study adds to our understanding of the adaptive evolution of AANAT and may provide molecular evidence for hibernation rhythm adaptation in bats. Arylalkylamine N-acetyltransferase (AANAT) is a crucial rate-limiting enzyme in the synthesis of melatonin. AANAT has been confirmed to be independently duplicated and inactivated in different animal taxa in order to adapt to the environment. However, the evolutionary forces associated with having a single copy of AANAT remain unclear. The greater horseshoe bat has a single copy of AANAT but exhibits different hibernation rhythms in various populations. We analyzed the adaptive evolution at the gene and protein levels of AANAT from three distinct genetic lineages in China: northeast (NE), central east (CE), and southwest (SW). The results revealed greater genetic diversity in the AANAT loci of the NE and CE lineage populations that have longer hibernation times, and there were two positive selection loci. The catalytic capacity of AANAT in the Liaoning population that underwent positive selection was significantly higher than that of the Yunnan population (p < 0.05). This difference may be related to the lower proportion of α helix and the variation in two interface residues. The adaptive evolution of AANAT was significantly correlated with climate and environment (p < 0.05). After controlling for geographical factors (latitude and altitude), the evolution of AANAT by the negative temperature factor was represented by the monthly mean temperature (r = −0.6, p < 0.05). The results identified the gene level variation, functional adaptation, and evolutionary driving factors of AANAT, provide an important foundation for further understanding the adaptive evolution of the single copy of AANAT in pteropods, and may offer evidence for adaptive hibernation rhythms in bats. [ABSTRACT FROM AUTHOR]

The importance of good performance in the logistics industry contributing towards a low-carbon economy is widely recognised. However, there are few studies on carbon emissions performance for the logistics industry, especially at the city level. Therefore, this study attempts to analyse the carbon emissions performance of the logistics industry at the city level by examining sixteen cities within Yunnan Province. In particular, the Data envelopment analysis (DEA) model and Malmquist index from both the static and dynamic perspective were explored. To further capture the driving factors of the carbon emissions performance in logistics, the Tobit model was applied to perform regression analysis. The results indicate that (1) with regards to static performance, two northwest cities, Nujiang and Diqing, have reached the technological frontier; (2) regarding dynamic performance, although six cities have improved, the average dynamic logistics carbon emissions performance of all the cities decreases by approximately 5.9% from 2011 to 2015; (3) in terms of driving factors, the economic development factor is found to be positively and significantly related to static carbon emissions performance, whereas others indicate negative and significant relationships. • We investigate carbon emissions performance in logistics at the city level. • An empirical study on sixteen cities in China is conducted. • Logistics-related carbon emissions of sixteen cities have increased from 2011 to 2015. • Carbon emissions performance in logistics vary across cities. • Carbon emissions performance in logistics attributes to different driving factors. [ABSTRACT FROM AUTHOR]